RS coding link BER simulation » History » Version 8

ABDALLAH, Hussein, 03/23/2016 02:39 PM

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h1. RS coding link BER simulation
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As we know that the Down link of voyage 1 use the RS(Reed–Solomon) coding when it navigated near the Uranus and Neptune. We change the coding module with RS coding.
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We simulate the BER with 4 RScoding: 
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* RS (15,11,2) coding rate = 0.73
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* RS (255,233,11) coding rate = 0.913
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* RS (255,239,8) coding rate = 0.937
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* RS (204,188,8) coding rate = 0.92 (shorten from ) RS(255,239,8)
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The interface of simulate is shown as following:
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!Communication_chain_interface_with_RS.jpg!
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And we get the simulate BER data with RS coding as shown in the table below:
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!BPSK_simulation_with_RS_results.jpg!
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We draw then all BER curves with several RS coding is shown in the figure below:
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!BER_with_RS.jpg!
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We can see from the figure above that the gain of RS coding is about *3 dB* with *BER = 1exp-5*, so the coding gain is much better than Golay coding which is about 1dB.
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But the RS coding rate is about 0.9, if decrease the coding rate we will get more coding gain. 
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So as an improvement, we decide to use a cascade coding in the next step in order to decrease the coding rate to 0.5 or 0.6.